Oscillation-detector.



C. D. BABGOGK.

OSGILLATION DETECTOR. APPLICATION nun 0012, 1907.

Patented Dec. 15, 1903.-

I 2 SHEETS-SHEET 1.

G. D. BABGOCK. OSIGILLATION DETECTOR.

* APPLICATION rman our. 2, 1907.

, 906,991. Patented De.15,1908.

2-BKBBTB-SHEET 2.

UNITED STATES PATENT FFIOE.

CLIFFORD D..BABGOGK, OF NEW YORK, N. Y., ASSIGNOR TO UNITED WI RELESSTELEGRAPH COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

OSCILLATION-DETECTOR.

To all whom it may concern:

Be it known that I, CLIFFORD D. BABCOOK, a citizen of the United States,and aresident of New York, in the county of New York and State of NewYork, have invented a new and useful Improvement inOscillation-Detectors, ofwhich the following is a specification.

My invention relates to detectors of the thermo-electric type for feebleelectric curby said elements. Experience has shown that thermo-electricoscillation detectors so constructed are not stable and soon lose theirsensltiveness, requiring therefore more or less frequent 'adjustmentorvarlatlon of the point at which one of the elements makes contact withthe other.

The object of the present invention is to provide an oscillationdetector of the thermoelectric type which shall not be-subject to theforegoing defects and limitations and which shall be capable ofdevelopingalarger amount of thermo-electric energy when. acted u on by agiven amount of electrical energy t an those of the type in which thereceived electrical energy is conveyed directly to the circuit whichincludesthe thermo-couple.

With this object in view my invention comprises a thermo-ele'ctriccouple consist-.

ing preferably of two elements widely separated in the thermo-electricscale and forming a perfect electrical contact, in combination withmeans such as a short conductor of small diameter associated with saidthermoelectric couple and adjacent thereto whereby the. energy of theoscillations to be detected may be converted into heat and therebyeleveto Ithe temperature of said thermo-electric cou e.

. e drawings which accompany and form apart of this specificationillustrate in diagram several embodiments of my invention whereby theforegoing objects'have been accomplished in practice; but it will beunderstood that 'said. embodiments which hare been qhosenforillustrating the haven-- Specification of Letters men-i. Applicationfiled October 2, 1907. Serial no. 395,492.

' related to the si Patented net. 15, 1902.

'tion may be subjected to a wide range of variation without departingfrom the principle thereof. 1

In the drawings, Figure 1 shows a thermoelectric couple having asignal-indicating device serially connected "therewith. Fig. 1 is an endviewfofone of the elements of a thermoeelectric couple shown in Fig. 1with the other element removed. Fig. 2 shows a -modification of thedetector shown in Fig. 1.

Fig. 3 shows a detectorhaving a plurality of thermo-electric couplesconnected in multiple with respect to the signal-indicating device. Fig.4 shows an oscillation detector consisting of a pluralityofflthermo-electrio couples connected in series. with respect to thesignal-indicating device. Fig. 5 shows an oscillation detectorconsisting of a plurality of thermo-electric couples each'havin itscircuit inductively related with thesign 4 indicating device; Fig. 6shows an oscillation'detector consisting of a thermo-electric coupleconnected in series with means for heating a second thermo-electriccouple'and a si al-indicating device associated with the atter. Fig. 7shows an oscillation de tector in which the circuit of a thermo-electriccouple is inductively related with a circuit which includes means forheating a sec- 0nd thermo-electric couple. Fig. 8 shows an oscillationdetector consisting of a thermoelectric couple having its circuitinductively al-indicating device. 9 showsa'n osci ation detectorconsisting of a plurality of thermo electric couples 0011-;

nccted in multiple-series with respect to a signal-indicating device.Fig.- 10' shows'an arrangement whereby one or more thermoelectriccouples may be associated with the circuit conveying the oscillations tobe detected. Fig. 11 is a fragmentary view showing one way in which theheating means may be adjusted with respect to the thermo-electric 0011lo. Fig. 12 shows partly inperspective an partly in diagram one wayinwhic a thermo-el'ectric couple may be employed to operate a relay.

In the figures, A. andB are thermo-electric elements, suchfor example,as bismuth and tellurium, respectively, or steel and gelenaor some othermetallic sulfid, respectively.

Fig.

However I do not limit myself as to the mar terial of said elementsinasmuch as they mayl be formed of any suitable materials whic lie farapart in the thermo-electric scale.

- turn of the conductor 0 is place increased and y means C may be ashort length of conductor of small diameter such for example as a bit ofone-half mil platinum wire or a bit of threequarter mil carbon filament.The conductor C may be arranged with respect to the junction of'theelements A B in any suitable manner. As shown in Fig. 1, it is bentaround said junction and in Fig. 2 a sin le around t 1e junction. Theelements A and B may have any suitable shape and as shown the area ofcontact of onewith the other is made small. This contact is a perfectelectricalcontact and may be made in any suitable for example, bysolderin other or by mechanica y pressing them in firm contact with eachother.

T is a signal-indicating device which may be associated with a circuitincluding the elements A and B in any suitable manner. The heatingconductor 0 is included 'in the circuit which carries the oscillationsto be detected. This circuit is shown as terminating at the points a andb. The points a and b may be'connected with a wireless telegraph orwireless telephone system, or other system in which the oscillations orcurrents to be detected are developed, in any of the usual ways in whichoscillation detectors are associated with such systems, as for example,by including the conductor a. C b in an antenna or in a tuned circuitassociated with such antenna.

.In Fig; 3 the thermo-electric couples A B, A B, A" B, are connected inmultiple with respect to the signal-indicating device T, which may be atele hone-receiver, and three heatin members C O" are connected inseries wit the circuit a b which conveys the oscillations to bedetected, said'heating members being associated with and adjacent to thethermo-electric couples, respectively. In Fig. 4 the threethermo-electrlcwouples are connected in series with the signalindieating device T. By means of the arrangementshown in Fig. 3 thethermo-electric current passing through the telephone T is of thearrangement shown in Fig. the thermo-elect'ric potential is increased.

As shown in Fig. 5 the signal-indicating device may be associated withtwo thermoelectric couples by means of the transformers M M which arearranged so that the currents developed in the circuit of the device Tare in the same direction.

In Fig. 6 the thermo-electric currents developed by the couple tor Owhich in turn causes the couple A B to develop thermo-electric currentswhich operate the telephone T. ,A modification of the arrangement shownin Fig. 6 is illustrated in Fig. 7 in which the thermo-electric currentsdeveloped by the couple A B are translated by the transformer M, whichmay i A B heat the conduc' I be a stepp transformer or a step-downtransformer, to the heating member C, which, by elevating thetemperature of the couple A B, causes said couple to develop i currentsin the circuit of the device T.

In Fig. 8, the device T is associated inductively with the circuit ofthe couple A B by means of the transformer M.

It will be'understood of course that the currents developed in thecircuit of the thermo-couples by oscillations created in the receivingsystem by electro-magnetic waves from wireless mitting systems, arepulsating currents which may of course be translated by a transformertothe signal-indicating device, as shown in Figs. 5 and 8 or to anotherheating element, as shown in Fig. 7.

In Fig. 9 the thermo-electric couples A B, A B, and A B are connected inmulti le series with respect to the signal-indicating device T.

In Fig. 10 the switch S which cooperates with the contacts 1 and 2 maybe employed to regulate the number of thermo-electric couples employedin a receiving system. The heating member C may be a much largerconductor than the heating member C. In such case when receiving signalsfrom nearl by stations, the heating member C may be out out in order toprotect the same from the received oscillations from said near-bystation which might fuse said member. The oscillations developed in thereceiving system by electro-magnetic waves transmitted from stationslocated at greater distances from the receiving system might not developsufficient heat in the conductor 0 to cause the development in thecircuit of the couple A B of a de- J tectable current, and therefore forlong distance communication, the switch S may be placed on contact 2 soas to bring the heating member G into operative relatlon with thecircuit a b.

'In Fig. 11 the heating member 0 is shown niounted upon the support Dwhich by means of the screw E may be moved with respect to thethermo-electric cou le, of which one element A, is shown in said figure.this construction is to prevent one or more of a number of. sets ofoscillations developed I by different transmitting systems in thecircuit a b from afiecting the thermo-electric I couple. By varying theposition of the heat- 1 ing member C with respect to cillations of smallamplitude and which therefore would raise the tem erature of the coupleto a relatively small egree, may be prevented from effecting thedevelopment of thermo-electric currents in the circuit of the couple byseparatin the couple and the heating member. vl hen the heating memberand con le are se arated sufficiently to prevent oscillations orelatively small amplitude from aflectin'g the couple, oscillatelegraphor telephone trans- The object ofthe couple, os

tions of relatively larger amplitude will develop in said heating membersuflicient heat to cause the couple to develop currents which at f andnormally held by the spring .9 so that be detected into'h'e'at and tionbetween A and B.

the heating member contacts withv the junc- U on the energization of thethermo-couple, t e magnet H, energized'by the thermo-electric currents,attracts the armature F and closes the circuit of the relay R andbattery G at the point I.

Inasmuch as the heating members 0 C C" must be rapidly responsive to theoscillations to be received, the thermo-couple with its heating membermay be placed in a suitable liquid or gaseous heat-absorbing medium.

I claim:

1. An oscillation detector comprising a thermo-electric couple and alocal circuit passing through the same in combination with meansassociated: with said couple and adjacent thereto for converting theenergy of the oscillations to be detected into heat and therebyelevating the temperature of said thermo-electric couple.

2. An oscillation detector comprising a local circuit and athermo-electric 'couple therein in combination with a conductorassociated therewith and adjacent thereto for converting the energy ofthe oscillations to thereby elevating the temperature of saidthermo-electric couple.

3. An oscillation detector com rising a local circuit and two elementswidl aly separated in the thermo-electric scale in said circuit andforming a perfect electrical contact in combination with meansassociated therewith and adjacent thereto for converting the energy ofthe oscillations to be detected into heat and thereby elevating thetemperature of said thermo-electric couple.

4. An oscillation detector comprising a thermo-electric couple, a localcircu t including the same, a signal-indicating device associated withsaid local circuit, a circuit independent of said thermo-clectriccouple, and means in said circuit for converting the "energy of theoscillations to be detected into heat and thereby elevating thetemperature of said thermo-electric couple.

5. An oscillation detector comprising a thermo-electric cou 1e, a localcircuit serially connected therewit a signal-indicating deviceassociated with said local circuit, a circuit independent of saidthermo-electric' couple and means included in the last mentioned circuitfor converting the energy of the oscillations to be detected into heatand thereby elevating'the temperature of said thermo-electric couple. Y

6. An oscillation detector comprising a plurality of thermo-electriccouples, a local circuit connecting said thermoelectric couples'inseries, a signal-indicating device associated with said local circuitand means associated with andadjacent to each of said thermo-electriccouples for convertin the energy of the oscillations to be detected intoheat and thereby elevating the temperature of said thermo-electriccouple.

In testimony whereof, I havehereunto subscribed my name.

CLIFFORD D.-BABCOCK.

Witnesses:

CHAS. J. ATTEND, LORETTA T. Noon.

